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-rw-r--r--kaldi_io/src/kaldi/hmm/hmm-topology.h172
-rw-r--r--kaldi_io/src/kaldi/hmm/hmm-utils.h295
-rw-r--r--kaldi_io/src/kaldi/hmm/posterior.h214
-rw-r--r--kaldi_io/src/kaldi/hmm/transition-model.h345
-rw-r--r--kaldi_io/src/kaldi/hmm/tree-accu.h69
5 files changed, 1095 insertions, 0 deletions
diff --git a/kaldi_io/src/kaldi/hmm/hmm-topology.h b/kaldi_io/src/kaldi/hmm/hmm-topology.h
new file mode 100644
index 0000000..53ca427
--- /dev/null
+++ b/kaldi_io/src/kaldi/hmm/hmm-topology.h
@@ -0,0 +1,172 @@
+// hmm/hmm-topology.h
+
+// Copyright 2009-2011 Microsoft Corporation
+
+// See ../../COPYING for clarification regarding multiple authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
+// WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,
+// MERCHANTABLITY OR NON-INFRINGEMENT.
+// See the Apache 2 License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef KALDI_HMM_HMM_TOPOLOGY_H_
+#define KALDI_HMM_HMM_TOPOLOGY_H_
+
+#include "base/kaldi-common.h"
+#include "tree/context-dep.h"
+#include "util/const-integer-set.h"
+
+
+namespace kaldi {
+
+
+/// \addtogroup hmm_group
+/// @{
+
+/*
+ // The following would be the text form for the "normal" HMM topology.
+ // Note that the first state is the start state, and the final state,
+ // which must have no output transitions and must be nonemitting, has
+ // an exit probability of one (no other state can have nonzero exit
+ // probability; you can treat the transition probability to the final
+ // state as an exit probability).
+ // Note also that it's valid to omit the "<PdfClass>" entry of the <State>, which
+ // will mean we won't have a pdf on that state [non-emitting state]. This is equivalent
+ // to setting the <PdfClass> to -1. We do this normally just for the final state.
+ // The Topology object can have multiple <TopologyEntry> blocks.
+ // This is useful if there are multiple types of topology in the system.
+
+ <Topology>
+ <TopologyEntry>
+ <ForPhones> 1 2 3 4 5 6 7 8 </ForPhones>
+ <State> 0 <PdfClass> 0
+ <Transition> 0 0.5
+ <Transition> 1 0.5
+ </State>
+ <State> 1 <PdfClass> 1
+ <Transition> 1 0.5
+ <Transition> 2 0.5
+ </State>
+ <State> 2 <PdfClass> 2
+ <Transition> 2 0.5
+ <Transition> 3 0.5
+ <Final> 0.5
+ </State>
+ <State> 3
+ </State>
+ </TopologyEntry>
+ </Topology>
+*/
+
+// kNoPdf is used where pdf_class or pdf would be used, to indicate,
+// none is there. Mainly useful in skippable models, but also used
+// for end states.
+// A caveat with nonemitting states is that their out-transitions
+// are not trainable, due to technical issues with the way
+// we decided to accumulate the stats. Any transitions arising from (*)
+// HMM states with "kNoPdf" as the label are second-class transitions,
+// They do not have "transition-states" or "transition-ids" associated
+// with them. They are used to create the FST version of the
+// HMMs, where they lead to epsilon arcs.
+// (*) "arising from" is a bit of a technical term here, due to the way
+// (if reorder == true), we put the transition-id associated with the
+// outward arcs of the state, on the input transition to the state.
+
+/// A constant used in the HmmTopology class as the \ref pdf_class "pdf-class"
+/// kNoPdf, which is used when a HMM-state is nonemitting (has no associated
+/// PDF).
+
+static const int32 kNoPdf = -1;
+
+/// A class for storing topology information for phones. See \ref hmm for context.
+/// This object is sometimes accessed in a file by itself, but more often
+/// as a class member of the Transition class (this is for convenience to reduce
+/// the number of files programs have to access).
+
+class HmmTopology {
+ public:
+ /// A structure defined inside HmmTopology to represent a HMM state.
+ struct HmmState {
+ /// The \ref pdf_class pdf-class, typically 0, 1 or 2 (the same as the HMM-state index),
+ /// but may be different to enable us to hardwire sharing of state, and may be
+ /// equal to \ref kNoPdf == -1 in order to specify nonemitting states (unusual).
+ int32 pdf_class;
+
+ /// A list of transitions. The first member of each pair is the index of
+ /// the next HmmState, and the second is the default transition probability
+ /// (before training).
+ std::vector<std::pair<int32, BaseFloat> > transitions;
+
+ explicit HmmState(int32 p): pdf_class(p) { }
+
+ bool operator == (const HmmState &other) const {
+ return (pdf_class == other.pdf_class && transitions == other.transitions);
+ }
+
+ HmmState(): pdf_class(-1) { }
+ };
+
+ /// TopologyEntry is a typedef that represents the topology of
+ /// a single (prototype) state.
+ typedef std::vector<HmmState> TopologyEntry;
+
+ void Read(std::istream &is, bool binary);
+ void Write(std::ostream &os, bool binary) const;
+
+ // Checks that the object is valid, and throw exception otherwise.
+ void Check();
+
+
+ /// Returns the topology entry (i.e. vector of HmmState) for this phone;
+ /// will throw exception if phone not covered by the topology.
+ const TopologyEntry &TopologyForPhone(int32 phone) const;
+
+ /// Returns the number of \ref pdf_class "pdf-classes" for this phone;
+ /// throws exception if phone not covered by this topology.
+ int32 NumPdfClasses(int32 phone) const;
+
+ /// Returns a reference to a sorted, unique list of phones covered by
+ /// the topology (these phones will be positive integers, and usually
+ /// contiguous and starting from one but the toolkit doesn't assume
+ /// they are contiguous).
+ const std::vector<int32> &GetPhones() const { return phones_; };
+
+ /// Outputs a vector of int32, indexed by phone, that gives the
+ /// number of \ref pdf_class pdf-classes for the phones; this is
+ /// used by tree-building code such as BuildTree().
+ void GetPhoneToNumPdfClasses(std::vector<int32> *phone2num_pdf_classes) const;
+
+ HmmTopology() {}
+
+ bool operator == (const HmmTopology &other) const {
+ return phones_ == other.phones_ && phone2idx_ == other.phone2idx_
+ && entries_ == other.entries_;
+ }
+ // Allow default assignment operator and copy constructor.
+ private:
+ std::vector<int32> phones_; // list of all phones we have topology for. Sorted, uniq. no epsilon (zero) phone.
+ std::vector<int32> phone2idx_; // map from phones to indexes into the entries vector (or -1 for not present).
+ std::vector<TopologyEntry> entries_;
+};
+
+
+/// This function returns a HmmTopology object giving a normal 3-state topology,
+/// covering all phones in the list "phones". This is mainly of use in testing
+/// code.
+HmmTopology GetDefaultTopology(const std::vector<int32> &phones);
+
+/// @} end "addtogroup hmm_group"
+
+
+} // end namespace kaldi
+
+
+#endif
diff --git a/kaldi_io/src/kaldi/hmm/hmm-utils.h b/kaldi_io/src/kaldi/hmm/hmm-utils.h
new file mode 100644
index 0000000..240f706
--- /dev/null
+++ b/kaldi_io/src/kaldi/hmm/hmm-utils.h
@@ -0,0 +1,295 @@
+// hmm/hmm-utils.h
+
+// Copyright 2009-2011 Microsoft Corporation
+
+// See ../../COPYING for clarification regarding multiple authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
+// WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,
+// MERCHANTABLITY OR NON-INFRINGEMENT.
+// See the Apache 2 License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef KALDI_HMM_HMM_UTILS_H_
+#define KALDI_HMM_HMM_UTILS_H_
+
+#include "hmm/hmm-topology.h"
+#include "hmm/transition-model.h"
+#include "lat/kaldi-lattice.h"
+
+namespace kaldi {
+
+
+/// \defgroup hmm_group_graph Classes and functions for creating FSTs from HMMs
+/// \ingroup hmm_group
+/// @{
+
+/// Configuration class for the GetHTransducer() function; see
+/// \ref hmm_graph_config for context.
+struct HTransducerConfig {
+ /// Transition log-prob scale, see \ref hmm_scale.
+ /// Note this doesn't apply to self-loops; GetHTransducer() does
+ /// not include self-loops.
+ BaseFloat transition_scale;
+
+ /// if true, we are constructing time-reversed FST: phone-seqs in ilabel_info
+ /// are backwards, and we want to output a backwards version of the HMM
+ /// corresponding to each phone. If reverse == true,
+ bool reverse;
+
+ /// This variable is only looked at if reverse == true. If reverse == true
+ /// and push_weights == true, then we push the weights in the reversed FSTs we create for each
+ /// phone HMM. This is only safe if the HMMs are probabilistic (i.e. not discriminatively
+ bool push_weights;
+
+ /// delta used if we do push_weights [only relevant if reverse == true
+ /// and push_weights == true].
+ BaseFloat push_delta;
+
+ HTransducerConfig():
+ transition_scale(1.0),
+ reverse(false),
+ push_weights(true),
+ push_delta(0.001)
+ { }
+
+ // Note-- this Register registers the easy-to-register options
+ // but not the "sym_type" which is an enum and should be handled
+ // separately in main().
+ void Register (OptionsItf *po) {
+ po->Register("transition-scale", &transition_scale,
+ "Scale of transition probs (relative to LM)");
+ po->Register("reverse", &reverse,
+ "Set true to build time-reversed FST.");
+ po->Register("push-weights", &push_weights,
+ "Push weights (only applicable if reverse == true)");
+ po->Register("push-delta", &push_delta,
+ "Delta used in pushing weights (only applicable if "
+ "reverse && push-weights");
+ }
+};
+
+
+struct HmmCacheHash {
+ int operator () (const std::pair<int32, std::vector<int32> >&p) const {
+ VectorHasher<int32> v;
+ int32 prime = 103049;
+ return prime*p.first + v(p.second);
+ }
+};
+
+/// HmmCacheType is a map from (central-phone, sequence of pdf-ids) to FST, used
+/// as cache in GetHmmAsFst, as an optimization.
+typedef unordered_map<std::pair<int32, std::vector<int32> >,
+ fst::VectorFst<fst::StdArc>*,
+ HmmCacheHash> HmmCacheType;
+
+
+/// Called by GetHTransducer() and probably will not need to be called directly;
+/// it creates the FST corresponding to the phone. Does not include self-loops;
+/// you have to call AddSelfLoops() for that. Result owned by caller.
+/// Returns an acceptor (i.e. ilabels, olabels identical) with transition-ids
+/// as the symbols.
+/// For documentation in context, see \ref hmm_graph_get_hmm_as_fst
+/// @param context_window A vector representing the phonetic context; see
+/// \ref tree_window "here" for explanation.
+/// @param ctx_dep The object that contains the phonetic decision-tree
+/// @param trans_model The transition-model object, which provides
+/// the mappings to transition-ids and also the transition
+/// probabilities.
+/// @param config Configuration object, see \ref HTransducerConfig.
+/// @param cache Object used as a lookaside buffer to save computation;
+/// if it finds that the object it needs is already there, it will
+/// just return a pointer value from "cache"-- not that this means
+/// you have to be careful not to delete things twice.
+
+fst::VectorFst<fst::StdArc> *GetHmmAsFst(
+ std::vector<int32> context_window,
+ const ContextDependencyInterface &ctx_dep,
+ const TransitionModel &trans_model,
+ const HTransducerConfig &config,
+ HmmCacheType *cache = NULL);
+
+/// Included mainly as a form of documentation, not used in any other code
+/// currently. Creates the FST with self-loops, and with fewer options.
+fst::VectorFst<fst::StdArc>*
+GetHmmAsFstSimple(std::vector<int32> context_window,
+ const ContextDependencyInterface &ctx_dep,
+ const TransitionModel &trans_model,
+ BaseFloat prob_scale);
+
+
+/**
+ * Returns the H tranducer; result owned by caller.
+ * See \ref hmm_graph_get_h_transducer. The H transducer has on the
+ * input transition-ids, and also possibly some disambiguation symbols, which
+ * will be put in disambig_syms. The output side contains the identifiers that
+ * are indexes into "ilabel_info" (these represent phones-in-context or
+ * disambiguation symbols). The ilabel_info vector allows GetHTransducer to map
+ * from symbols to phones-in-context (i.e. phonetic context windows). Any
+ * singleton symbols in the ilabel_info vector which are not phones, will be
+ * treated as disambiguation symbols. [Not all recipes use these]. The output
+ * "disambig_syms_left" will be set to a list of the disambiguation symbols on
+ * the input of the transducer (i.e. same symbol type as whatever is on the
+ * input of the transducer
+ */
+fst::VectorFst<fst::StdArc>*
+GetHTransducer (const std::vector<std::vector<int32> > &ilabel_info,
+ const ContextDependencyInterface &ctx_dep,
+ const TransitionModel &trans_model,
+ const HTransducerConfig &config,
+ std::vector<int32> *disambig_syms_left);
+
+/**
+ * GetIlabelMapping produces a mapping that's similar to HTK's logical-to-physical
+ * model mapping (i.e. the xwrd.clustered.mlist files). It groups together
+ * "logical HMMs" (i.e. in our world, phonetic context windows) that share the
+ * same sequence of transition-ids. This can be used in an
+ * optional graph-creation step that produces a remapped form of CLG that can be
+ * more productively determinized and minimized. This is used in the command-line program
+ * make-ilabel-transducer.cc.
+ * @param ilabel_info_old [in] The original \ref tree_ilabel "ilabel_info" vector
+ * @param ctx_dep [in] The tree
+ * @param trans_model [in] The transition-model object
+ * @param old2new_map [out] The output; this vector, which is of size equal to the
+ * number of new labels, is a mapping to the old labels such that we could
+ * create a vector ilabel_info_new such that
+ * ilabel_info_new[i] == ilabel_info_old[old2new_map[i]]
+ */
+void GetIlabelMapping (const std::vector<std::vector<int32> > &ilabel_info_old,
+ const ContextDependencyInterface &ctx_dep,
+ const TransitionModel &trans_model,
+ std::vector<int32> *old2new_map);
+
+
+
+/**
+ * For context, see \ref hmm_graph_add_self_loops. Expands an FST that has been
+ * built without self-loops, and adds the self-loops (it also needs to modify
+ * the probability of the non-self-loop ones, as the graph without self-loops
+ * was created in such a way that it was stochastic). Note that the
+ * disambig_syms will be empty in some recipes (e.g. if you already removed
+ * the disambiguation symbols).
+ * @param trans_model [in] Transition model
+ * @param disambig_syms [in] Sorted, uniq list of disambiguation symbols, required
+ * if the graph contains disambiguation symbols but only needed for sanity checks.
+ * @param self_loop_scale [in] Transition-probability scale for self-loops; c.f.
+ * \ref hmm_scale
+ * @param reorder [in] If true, reorders the transitions (see \ref hmm_reorder).
+ * @param fst [in, out] The FST to be modified.
+ */
+void AddSelfLoops(const TransitionModel &trans_model,
+ const std::vector<int32> &disambig_syms, // used as a check only.
+ BaseFloat self_loop_scale,
+ bool reorder, // true->dan-style, false->lukas-style.
+ fst::VectorFst<fst::StdArc> *fst);
+
+/**
+ * Adds transition-probs, with the supplied
+ * scales (see \ref hmm_scale), to the graph.
+ * Useful if you want to create a graph without transition probs, then possibly
+ * train the model (including the transition probs) but keep the graph fixed,
+ * and add back in the transition probs. It assumes the fst has transition-ids
+ * on it. It is not an error if the FST has no states (nothing will be done).
+ * @param trans_model [in] The transition model
+ * @param disambig_syms [in] A list of disambiguation symbols, required if the
+ * graph has disambiguation symbols on its input but only
+ * used for checks.
+ * @param transition_scale [in] A scale on transition-probabilities apart from
+ * those involving self-loops; see \ref hmm_scale.
+ * @param self_loop_scale [in] A scale on self-loop transition probabilities;
+ * see \ref hmm_scale.
+ * @param fst [in, out] The FST to be modified.
+ */
+void AddTransitionProbs(const TransitionModel &trans_model,
+ const std::vector<int32> &disambig_syms,
+ BaseFloat transition_scale,
+ BaseFloat self_loop_scale,
+ fst::VectorFst<fst::StdArc> *fst);
+
+/**
+ This is as AddSelfLoops(), but operates on a Lattice, where
+ it affects the graph part of the weight (the first element
+ of the pair). */
+void AddTransitionProbs(const TransitionModel &trans_model,
+ BaseFloat transition_scale,
+ BaseFloat self_loop_scale,
+ Lattice *lat);
+
+
+/// Returns a transducer from pdfs plus one (input) to transition-ids (output).
+/// Currenly of use only for testing.
+fst::VectorFst<fst::StdArc>*
+GetPdfToTransitionIdTransducer(const TransitionModel &trans_model);
+
+/// Converts all transition-ids in the FST to pdfs plus one.
+/// Placeholder: not implemented yet!
+void ConvertTransitionIdsToPdfs(const TransitionModel &trans_model,
+ const std::vector<int32> &disambig_syms,
+ fst::VectorFst<fst::StdArc> *fst);
+
+/// @} end "defgroup hmm_group_graph"
+
+/// \addtogroup hmm_group
+/// @{
+
+/// SplitToPhones splits up the TransitionIds in "alignment" into their
+/// individual phones (one vector per instance of a phone). At output,
+/// the sum of the sizes of the vectors in split_alignment will be the same
+/// as the corresponding sum for "alignment". The function returns
+/// true on success. If the alignment appears to be incomplete, e.g.
+/// not ending at the end-state of a phone, it will still break it up into
+/// phones but it will return false. For more serious errors it will
+/// die or throw an exception.
+/// This function works out by itself whether the graph was created
+/// with "reordering" (dan-style graph), and just does the right thing.
+
+bool SplitToPhones(const TransitionModel &trans_model,
+ const std::vector<int32> &alignment,
+ std::vector<std::vector<int32> > *split_alignment);
+
+/// ConvertAlignment converts an alignment that was created using one
+/// model, to another model. They must use a compatible topology (so we
+/// know the state alignments of the new model).
+/// It returns false if it could not be split to phones (probably
+/// because the alignment was partial), but for other kinds of
+/// error that are more likely a coding error, it will throw
+/// an exception.
+bool ConvertAlignment(const TransitionModel &old_trans_model,
+ const TransitionModel &new_trans_model,
+ const ContextDependencyInterface &new_ctx_dep,
+ const std::vector<int32> &old_alignment,
+ const std::vector<int32> *phone_map, // may be NULL
+ std::vector<int32> *new_alignment);
+
+// ConvertPhnxToProns is only needed in bin/phones-to-prons.cc and
+// isn't closely related with HMMs, but we put it here as there isn't
+// any other obvious place for it and it needs to be tested.
+// This function takes a phone-sequence with word-start and word-end
+// markers in it, and a word-sequence, and outputs the pronunciations
+// "prons"... the format of "prons" is, each element is a vector,
+// where the first element is the word (or zero meaning no word, e.g.
+// for optional silence introduced by the lexicon), and the remaining
+// elements are the phones in the word's pronunciation.
+// It returns false if it encounters a problem of some kind, e.g.
+// if the phone-sequence doesn't seem to have the right number of
+// words in it.
+bool ConvertPhnxToProns(const std::vector<int32> &phnx,
+ const std::vector<int32> &words,
+ int32 word_start_sym,
+ int32 word_end_sym,
+ std::vector<std::vector<int32> > *prons);
+
+/// @} end "addtogroup hmm_group"
+
+} // end namespace kaldi
+
+
+#endif
diff --git a/kaldi_io/src/kaldi/hmm/posterior.h b/kaldi_io/src/kaldi/hmm/posterior.h
new file mode 100644
index 0000000..be73be9
--- /dev/null
+++ b/kaldi_io/src/kaldi/hmm/posterior.h
@@ -0,0 +1,214 @@
+// hmm/posterior.h
+
+// Copyright 2009-2011 Microsoft Corporation
+// 2013-2014 Johns Hopkins University (author: Daniel Povey)
+// 2014 Guoguo Chen
+
+
+// See ../../COPYING for clarification regarding multiple authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
+// WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,
+// MERCHANTABLITY OR NON-INFRINGEMENT.
+// See the Apache 2 License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef KALDI_HMM_POSTERIOR_H_
+#define KALDI_HMM_POSTERIOR_H_
+
+#include "base/kaldi-common.h"
+#include "tree/context-dep.h"
+#include "util/const-integer-set.h"
+#include "util/kaldi-table.h"
+#include "hmm/transition-model.h"
+
+
+namespace kaldi {
+
+
+/// \addtogroup posterior_group
+/// @{
+
+/// Posterior is a typedef for storing acoustic-state (actually, transition-id)
+/// posteriors over an utterance. The "int32" is a transition-id, and the BaseFloat
+/// is a probability (typically between zero and one).
+typedef std::vector<std::vector<std::pair<int32, BaseFloat> > > Posterior;
+
+/// GaussPost is a typedef for storing Gaussian-level posteriors for an utterance.
+/// the "int32" is a transition-id, and the Vector<BaseFloat> is a vector of
+/// Gaussian posteriors.
+/// WARNING: We changed "int32" from transition-id to pdf-id, and the change is
+/// applied for all programs using GaussPost. This is for efficiency purpose. We
+/// also changed the name slightly from GauPost to GaussPost to reduce the
+/// chance that the change will go un-noticed in downstream code.
+typedef std::vector<std::vector<std::pair<int32, Vector<BaseFloat> > > > GaussPost;
+
+
+// PosteriorHolder is a holder for Posterior, which is
+// std::vector<std::vector<std::pair<int32, BaseFloat> > >
+// This is used for storing posteriors of transition id's for an
+// utterance.
+class PosteriorHolder {
+ public:
+ typedef Posterior T;
+
+ PosteriorHolder() { }
+
+ static bool Write(std::ostream &os, bool binary, const T &t);
+
+ void Clear() { Posterior tmp; std::swap(tmp, t_); }
+
+ // Reads into the holder.
+ bool Read(std::istream &is);
+
+ // Kaldi objects always have the stream open in binary mode for
+ // reading.
+ static bool IsReadInBinary() { return true; }
+
+ const T &Value() const { return t_; }
+
+ private:
+ KALDI_DISALLOW_COPY_AND_ASSIGN(PosteriorHolder);
+ T t_;
+};
+
+
+// GaussPostHolder is a holder for GaussPost, which is
+// std::vector<std::vector<std::pair<int32, Vector<BaseFloat> > > >
+// This is used for storing posteriors of transition id's for an
+// utterance.
+class GaussPostHolder {
+ public:
+ typedef GaussPost T;
+
+ GaussPostHolder() { }
+
+ static bool Write(std::ostream &os, bool binary, const T &t);
+
+ void Clear() { GaussPost tmp; std::swap(tmp, t_); }
+
+ // Reads into the holder.
+ bool Read(std::istream &is);
+
+ // Kaldi objects always have the stream open in binary mode for
+ // reading.
+ static bool IsReadInBinary() { return true; }
+
+ const T &Value() const { return t_; }
+
+ private:
+ KALDI_DISALLOW_COPY_AND_ASSIGN(GaussPostHolder);
+ T t_;
+};
+
+
+// Posterior is a typedef: vector<vector<pair<int32, BaseFloat> > >,
+// representing posteriors over (typically) transition-ids for an
+// utterance.
+typedef TableWriter<PosteriorHolder> PosteriorWriter;
+typedef SequentialTableReader<PosteriorHolder> SequentialPosteriorReader;
+typedef RandomAccessTableReader<PosteriorHolder> RandomAccessPosteriorReader;
+
+
+// typedef std::vector<std::vector<std::pair<int32, Vector<BaseFloat> > > > GaussPost;
+typedef TableWriter<GaussPostHolder> GaussPostWriter;
+typedef SequentialTableReader<GaussPostHolder> SequentialGaussPostReader;
+typedef RandomAccessTableReader<GaussPostHolder> RandomAccessGaussPostReader;
+
+
+/// Scales the BaseFloat (weight) element in the posterior entries.
+void ScalePosterior(BaseFloat scale, Posterior *post);
+
+/// Returns the total of all the weights in "post".
+BaseFloat TotalPosterior(const Posterior &post);
+
+/// Returns true if the two lists of pairs have no common .first element.
+bool PosteriorEntriesAreDisjoint(
+ const std::vector<std::pair<int32, BaseFloat> > &post_elem1,
+ const std::vector<std::pair<int32, BaseFloat> > &post_elem2);
+
+
+/// Merge two sets of posteriors, which must have the same length. If "merge"
+/// is true, it will make a common entry whenever there are duplicated entries,
+/// adding up the weights. If "drop_frames" is true, for frames where the
+/// two sets of posteriors were originally disjoint, makes no entries for that
+/// frame (relates to frame dropping, or drop_frames, see Vesely et al, ICASSP
+/// 2013). Returns the number of frames for which the two posteriors were
+/// disjoint (i.e. no common transition-ids or whatever index we are using).
+int32 MergePosteriors(const Posterior &post1,
+ const Posterior &post2,
+ bool merge,
+ bool drop_frames,
+ Posterior *post);
+
+/// Given a vector of log-likelihoods (typically of Gaussians in a GMM
+/// but could be of pdf-ids), a number gselect >= 1 and a minimum posterior
+/// 0 <= min_post < 1, it gets the posterior for each element of log-likes
+/// by applying Softmax(), then prunes the posteriors using "gselect" and
+/// "min_post" (keeping at least one), and outputs the result into
+/// "post_entry", sorted from greatest to least posterior.
+/// Returns the total log-likelihood (the output of calling ApplySoftMax()
+/// on a copy of log_likes).
+BaseFloat VectorToPosteriorEntry(
+ const VectorBase<BaseFloat> &log_likes,
+ int32 num_gselect,
+ BaseFloat min_post,
+ std::vector<std::pair<int32, BaseFloat> > *post_entry);
+
+/// Convert an alignment to a posterior (with a scale of 1.0 on
+/// each entry).
+void AlignmentToPosterior(const std::vector<int32> &ali,
+ Posterior *post);
+
+/// Sorts posterior entries so that transition-ids with same pdf-id are next to
+/// each other.
+void SortPosteriorByPdfs(const TransitionModel &tmodel,
+ Posterior *post);
+
+
+/// Converts a posterior over transition-ids to be a posterior
+/// over pdf-ids.
+void ConvertPosteriorToPdfs(const TransitionModel &tmodel,
+ const Posterior &post_in,
+ Posterior *post_out);
+
+/// Converts a posterior over transition-ids to be a posterior
+/// over phones.
+void ConvertPosteriorToPhones(const TransitionModel &tmodel,
+ const Posterior &post_in,
+ Posterior *post_out);
+
+/// Weight any silence phones in the posterior (i.e. any phones
+/// in the set "silence_set" by scale "silence_scale".
+/// The interface was changed in Feb 2014 to do the modification
+/// "in-place" rather than having separate input and output.
+void WeightSilencePost(const TransitionModel &trans_model,
+ const ConstIntegerSet<int32> &silence_set,
+ BaseFloat silence_scale,
+ Posterior *post);
+
+/// This is similar to WeightSilencePost, except that on each frame it
+/// works out the amount by which the overall posterior would be reduced,
+/// and scales down everything on that frame by the same amount. It
+/// has the effect that frames that are mostly silence get down-weighted.
+/// The interface was changed in Feb 2014 to do the modification
+/// "in-place" rather than having separate input and output.
+void WeightSilencePostDistributed(const TransitionModel &trans_model,
+ const ConstIntegerSet<int32> &silence_set,
+ BaseFloat silence_scale,
+ Posterior *post);
+
+/// @} end "addtogroup posterior_group"
+
+
+} // end namespace kaldi
+
+
+#endif
diff --git a/kaldi_io/src/kaldi/hmm/transition-model.h b/kaldi_io/src/kaldi/hmm/transition-model.h
new file mode 100644
index 0000000..ccc4f11
--- /dev/null
+++ b/kaldi_io/src/kaldi/hmm/transition-model.h
@@ -0,0 +1,345 @@
+// hmm/transition-model.h
+
+// Copyright 2009-2012 Microsoft Corporation
+// Johns Hopkins University (author: Guoguo Chen)
+
+// See ../../COPYING for clarification regarding multiple authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
+// WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,
+// MERCHANTABLITY OR NON-INFRINGEMENT.
+// See the Apache 2 License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef KALDI_HMM_TRANSITION_MODEL_H_
+#define KALDI_HMM_TRANSITION_MODEL_H_
+
+#include "base/kaldi-common.h"
+#include "tree/context-dep.h"
+#include "util/const-integer-set.h"
+#include "fst/fst-decl.h" // forward declarations.
+#include "hmm/hmm-topology.h"
+#include "itf/options-itf.h"
+
+namespace kaldi {
+
+/// \addtogroup hmm_group
+/// @{
+
+// The class TransitionModel is a repository for the transition probabilities.
+// It also handles certain integer mappings.
+// The basic model is as follows. Each phone has a HMM topology defined in
+// hmm-topology.h. Each HMM-state of each of these phones has a number of
+// transitions (and final-probs) out of it. Each HMM-state defined in the
+// HmmTopology class has an associated "pdf_class". This gets replaced with
+// an actual pdf-id via the tree. The transition model associates the
+// transition probs with the (phone, HMM-state, pdf-id). We associate with
+// each such triple a transition-state. Each
+// transition-state has a number of associated probabilities to estimate;
+// this depends on the number of transitions/final-probs in the topology for
+// that (phone, HMM-state). Each probability has an associated transition-index.
+// We associate with each (transition-state, transition-index) a unique transition-id.
+// Each individual probability estimated by the transition-model is asociated with a
+// transition-id.
+//
+// List of the various types of quantity referred to here and what they mean:
+// phone: a phone index (1, 2, 3 ...)
+// HMM-state: a number (0, 1, 2...) that indexes TopologyEntry (see hmm-topology.h)
+// pdf-id: a number output by the Compute function of ContextDependency (it
+// indexes pdf's). Zero-based.
+// transition-state: the states for which we estimate transition probabilities for transitions
+// out of them. In some topologies, will map one-to-one with pdf-ids.
+// One-based, since it appears on FSTs.
+// transition-index: identifier of a transition (or final-prob) in the HMM. Indexes the
+// "transitions" vector in HmmTopology::HmmState. [if it is out of range,
+// equal to transitions.size(), it refers to the final-prob.]
+// Zero-based.
+// transition-id: identifier of a unique parameter of the TransitionModel.
+// Associated with a (transition-state, transition-index) pair.
+// One-based, since it appears on FSTs.
+//
+// List of the possible mappings TransitionModel can do:
+// (phone, HMM-state, pdf-id) -> transition-state
+// (transition-state, transition-index) -> transition-id
+// Reverse mappings:
+// transition-id -> transition-state
+// transition-id -> transition-index
+// transition-state -> phone
+// transition-state -> HMM-state
+// transition-state -> pdf-id
+//
+// The main things the TransitionModel object can do are:
+// Get initialized (need ContextDependency and HmmTopology objects).
+// Read/write.
+// Update [given a vector of counts indexed by transition-id].
+// Do the various integer mappings mentioned above.
+// Get the probability (or log-probability) associated with a particular transition-id.
+
+
+// Note: this was previously called TransitionUpdateConfig.
+struct MleTransitionUpdateConfig {
+ BaseFloat floor;
+ BaseFloat mincount;
+ bool share_for_pdfs; // If true, share all transition parameters that have the same pdf.
+ MleTransitionUpdateConfig(BaseFloat floor = 0.01,
+ BaseFloat mincount = 5.0,
+ bool share_for_pdfs = false):
+ floor(floor), mincount(mincount), share_for_pdfs(share_for_pdfs) {}
+
+ void Register (OptionsItf *po) {
+ po->Register("transition-floor", &floor,
+ "Floor for transition probabilities");
+ po->Register("transition-min-count", &mincount,
+ "Minimum count required to update transitions from a state");
+ po->Register("share-for-pdfs", &share_for_pdfs,
+ "If true, share all transition parameters where the states "
+ "have the same pdf.");
+ }
+};
+
+struct MapTransitionUpdateConfig {
+ BaseFloat tau;
+ bool share_for_pdfs; // If true, share all transition parameters that have the same pdf.
+ MapTransitionUpdateConfig(): tau(5.0), share_for_pdfs(false) { }
+
+ void Register (OptionsItf *po) {
+ po->Register("transition-tau", &tau, "Tau value for MAP estimation of transition "
+ "probabilities.");
+ po->Register("share-for-pdfs", &share_for_pdfs,
+ "If true, share all transition parameters where the states "
+ "have the same pdf.");
+ }
+};
+
+class TransitionModel {
+
+ public:
+ /// Initialize the object [e.g. at the start of training].
+ /// The class keeps a copy of the HmmTopology object, but not
+ /// the ContextDependency object.
+ TransitionModel(const ContextDependency &ctx_dep,
+ const HmmTopology &hmm_topo);
+
+
+ /// Constructor that takes no arguments: typically used prior to calling Read.
+ TransitionModel() { }
+
+ void Read(std::istream &is, bool binary); // note, no symbol table: topo object always read/written w/o symbols.
+ void Write(std::ostream &os, bool binary) const;
+
+
+ /// return reference to HMM-topology object.
+ const HmmTopology &GetTopo() const { return topo_; }
+
+ /// \name Integer mapping functions
+ /// @{
+
+ int32 TripleToTransitionState(int32 phone, int32 hmm_state, int32 pdf) const;
+ int32 PairToTransitionId(int32 trans_state, int32 trans_index) const;
+ int32 TransitionIdToTransitionState(int32 trans_id) const;
+ int32 TransitionIdToTransitionIndex(int32 trans_id) const;
+ int32 TransitionStateToPhone(int32 trans_state) const;
+ int32 TransitionStateToHmmState(int32 trans_state) const;
+ int32 TransitionStateToPdf(int32 trans_state) const;
+ int32 SelfLoopOf(int32 trans_state) const; // returns the self-loop transition-id, or zero if
+ // this state doesn't have a self-loop.
+
+ inline int32 TransitionIdToPdf(int32 trans_id) const;
+ int32 TransitionIdToPhone(int32 trans_id) const;
+ int32 TransitionIdToPdfClass(int32 trans_id) const;
+ int32 TransitionIdToHmmState(int32 trans_id) const;
+
+ /// @}
+
+ bool IsFinal(int32 trans_id) const; // returns true if this trans_id goes to the final state
+ // (which is bound to be nonemitting).
+ bool IsSelfLoop(int32 trans_id) const; // return true if this trans_id corresponds to a self-loop.
+
+ /// Returns the total number of transition-ids (note, these are one-based).
+ inline int32 NumTransitionIds() const { return id2state_.size()-1; }
+
+ /// Returns the number of transition-indices for a particular transition-state.
+ /// Note: "Indices" is the plural of "index". Index is not the same as "id",
+ /// here. A transition-index is a zero-based offset into the transitions
+ /// out of a particular transition state.
+ int32 NumTransitionIndices(int32 trans_state) const;
+
+ /// Returns the total number of transition-states (note, these are one-based).
+ int32 NumTransitionStates() const { return triples_.size(); }
+
+ // NumPdfs() actually returns the highest-numbered pdf we ever saw, plus one.
+ // In normal cases this should equal the number of pdfs in the system, but if you
+ // initialized this object with fewer than all the phones, and it happens that
+ // an unseen phone has the highest-numbered pdf, this might be different.
+ int32 NumPdfs() const { return num_pdfs_; }
+
+ // This loops over the triples and finds the highest phone index present. If
+ // the FST symbol table for the phones is created in the expected way, i.e.:
+ // starting from 1 (<eps> is 0) and numbered contiguously till the last phone,
+ // this will be the total number of phones.
+ int32 NumPhones() const;
+
+ /// Returns a sorted, unique list of phones.
+ const std::vector<int32> &GetPhones() const { return topo_.GetPhones(); }
+
+ // Transition-parameter-getting functions:
+ BaseFloat GetTransitionProb(int32 trans_id) const;
+ BaseFloat GetTransitionLogProb(int32 trans_id) const;
+
+ // The following functions are more specialized functions for getting
+ // transition probabilities, that are provided for convenience.
+
+ /// Returns the log-probability of a particular non-self-loop transition
+ /// after subtracting the probability mass of the self-loop and renormalizing;
+ /// will crash if called on a self-loop. Specifically:
+ /// for non-self-loops it returns the log of that prob divided by (1 minus
+ /// self-loop-prob-for-that-state).
+ BaseFloat GetTransitionLogProbIgnoringSelfLoops(int32 trans_id) const;
+
+ /// Returns the log-prob of the non-self-loop probability
+ /// mass for this transition state. (you can get the self-loop prob, if a self-loop
+ /// exists, by calling GetTransitionLogProb(SelfLoopOf(trans_state)).
+ BaseFloat GetNonSelfLoopLogProb(int32 trans_state) const;
+
+ /// Does Maximum Likelihood estimation. The stats are counts/weights, indexed
+ /// by transition-id. This was previously called Update().
+ void MleUpdate(const Vector<double> &stats,
+ const MleTransitionUpdateConfig &cfg,
+ BaseFloat *objf_impr_out,
+ BaseFloat *count_out);
+
+ /// Does Maximum A Posteriori (MAP) estimation. The stats are counts/weights,
+ /// indexed by transition-id.
+ void MapUpdate(const Vector<double> &stats,
+ const MapTransitionUpdateConfig &cfg,
+ BaseFloat *objf_impr_out,
+ BaseFloat *count_out);
+
+ /// Print will print the transition model in a human-readable way, for purposes of human
+ /// inspection. The "occs" are optional (they are indexed by pdf-id).
+ void Print(std::ostream &os,
+ const std::vector<std::string> &phone_names,
+ const Vector<double> *occs = NULL);
+
+
+ void InitStats(Vector<double> *stats) const { stats->Resize(NumTransitionIds()+1); }
+
+ void Accumulate(BaseFloat prob, int32 trans_id, Vector<double> *stats) const {
+ KALDI_ASSERT(trans_id <= NumTransitionIds());
+ (*stats)(trans_id) += prob;
+ // This is trivial and doesn't require class members, but leaves us more open
+ // to design changes than doing it manually.
+ }
+
+ /// returns true if all the integer class members are identical (but does not
+ /// compare the transition probabilities.
+ bool Compatible(const TransitionModel &other) const;
+
+ private:
+ void MleUpdateShared(const Vector<double> &stats,
+ const MleTransitionUpdateConfig &cfg,
+ BaseFloat *objf_impr_out, BaseFloat *count_out);
+ void MapUpdateShared(const Vector<double> &stats,
+ const MapTransitionUpdateConfig &cfg,
+ BaseFloat *objf_impr_out, BaseFloat *count_out);
+ void ComputeTriples(const ContextDependency &ctx_dep); // called from constructor. initializes triples_.
+ void ComputeDerived(); // called from constructor and Read function: computes state2id_ and id2state_.
+ void ComputeDerivedOfProbs(); // computes quantities derived from log-probs (currently just
+ // non_self_loop_log_probs_; called whenever log-probs change.
+ void InitializeProbs(); // called from constructor.
+ void Check() const;
+
+ struct Triple {
+ int32 phone;
+ int32 hmm_state;
+ int32 pdf;
+ Triple() { }
+ Triple(int32 phone, int32 hmm_state, int32 pdf):
+ phone(phone), hmm_state(hmm_state), pdf(pdf) { }
+ bool operator < (const Triple &other) const {
+ if (phone < other.phone) return true;
+ else if (phone > other.phone) return false;
+ else if (hmm_state < other.hmm_state) return true;
+ else if (hmm_state > other.hmm_state) return false;
+ else return pdf < other.pdf;
+ }
+ bool operator == (const Triple &other) const {
+ return (phone == other.phone && hmm_state == other.hmm_state
+ && pdf == other.pdf);
+ }
+ };
+
+ HmmTopology topo_;
+
+ /// Triples indexed by transition state minus one;
+ /// the triples are in sorted order which allows us to do the reverse mapping from
+ /// triple to transition state
+ std::vector<Triple> triples_;
+
+ /// Gives the first transition_id of each transition-state; indexed by
+ /// the transition-state. Array indexed 1..num-transition-states+1 (the last one
+ /// is needed so we can know the num-transitions of the last transition-state.
+ std::vector<int32> state2id_;
+
+ /// For each transition-id, the corresponding transition
+ /// state (indexed by transition-id).
+ std::vector<int32> id2state_;
+
+ /// For each transition-id, the corresponding log-prob. Indexed by transition-id.
+ Vector<BaseFloat> log_probs_;
+
+ /// For each transition-state, the log of (1 - self-loop-prob). Indexed by
+ /// transition-state.
+ Vector<BaseFloat> non_self_loop_log_probs_;
+
+ /// This is actually one plus the highest-numbered pdf we ever got back from the
+ /// tree (but the tree numbers pdfs contiguously from zero so this is the number
+ /// of pdfs).
+ int32 num_pdfs_;
+
+
+ DISALLOW_COPY_AND_ASSIGN(TransitionModel);
+
+};
+
+inline int32 TransitionModel::TransitionIdToPdf(int32 trans_id) const {
+ // If a lot of time is spent here we may create an extra array
+ // to handle this.
+ KALDI_ASSERT(static_cast<size_t>(trans_id) < id2state_.size() &&
+ "Likely graph/model mismatch (graph built from wrong model?)");
+ int32 trans_state = id2state_[trans_id];
+ return triples_[trans_state-1].pdf;
+}
+
+/// Works out which pdfs might correspond to the given phones. Will return true
+/// if these pdfs correspond *just* to these phones, false if these pdfs are also
+/// used by other phones.
+/// @param trans_model [in] Transition-model used to work out this information
+/// @param phones [in] A sorted, uniq vector that represents a set of phones
+/// @param pdfs [out] Will be set to a sorted, uniq list of pdf-ids that correspond
+/// to one of this set of phones.
+/// @return Returns true if all of the pdfs output to "pdfs" correspond to phones from
+/// just this set (false if they may be shared with phones outside this set).
+bool GetPdfsForPhones(const TransitionModel &trans_model,
+ const std::vector<int32> &phones,
+ std::vector<int32> *pdfs);
+
+/// Works out which phones might correspond to the given pdfs. Similar to the
+/// above GetPdfsForPhones(, ,)
+bool GetPhonesForPdfs(const TransitionModel &trans_model,
+ const std::vector<int32> &pdfs,
+ std::vector<int32> *phones);
+/// @}
+
+
+} // end namespace kaldi
+
+
+#endif
diff --git a/kaldi_io/src/kaldi/hmm/tree-accu.h b/kaldi_io/src/kaldi/hmm/tree-accu.h
new file mode 100644
index 0000000..d571762
--- /dev/null
+++ b/kaldi_io/src/kaldi/hmm/tree-accu.h
@@ -0,0 +1,69 @@
+// hmm/tree-accu.h
+
+// Copyright 2009-2011 Microsoft Corporation
+// 2013 Johns Hopkins University (author: Daniel Povey)
+
+// See ../../COPYING for clarification regarding multiple authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+// http://www.apache.org/licenses/LICENSE-2.0
+
+// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
+// WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,
+// MERCHANTABLITY OR NON-INFRINGEMENT.
+// See the Apache 2 License for the specific language governing permissions and
+// limitations under the License.
+#ifndef KALDI_HMM_TREE_ACCU_H_
+#define KALDI_HMM_TREE_ACCU_H_
+
+#include <cctype> // For isspace.
+#include <limits>
+#include "base/kaldi-common.h"
+#include "hmm/transition-model.h"
+#include "tree/clusterable-classes.h"
+#include "tree/build-tree-questions.h" // needed for this typedef:
+// typedef std::vector<std::pair<EventVector, Clusterable*> > BuildTreeStatsType;
+
+namespace kaldi {
+
+/// \ingroup tree_group_top
+/// @{
+
+
+/// Accumulates the stats needed for training context-dependency trees (in the
+/// "normal" way). It adds to 'stats' the stats obtained from this file. Any
+/// new GaussClusterable* pointers in "stats" will be allocated with "new".
+
+void AccumulateTreeStats(const TransitionModel &trans_model,
+ BaseFloat var_floor,
+ int N, // context window size.
+ int P, // central position.
+ const std::vector<int32> &ci_phones, // sorted
+ const std::vector<int32> &alignment,
+ const Matrix<BaseFloat> &features,
+ const std::vector<int32> *phone_map, // or NULL
+ std::map<EventType, GaussClusterable*> *stats);
+
+
+
+/*** Read a mapping from one phone set to another. The phone map file has lines
+ of the form <old-phone> <new-phone>, where both entries are integers, usually
+ nonzero (but this is not enforced). This program will crash if the input is
+ invalid, e.g. there are multiple inconsistent entries for the same old phone.
+ The output vector "phone_map" will be indexed by old-phone and will contain
+ the corresponding new-phone, or -1 for any entry that was not defined. */
+
+void ReadPhoneMap(std::string phone_map_rxfilename,
+ std::vector<int32> *phone_map);
+
+
+
+/// @}
+
+} // end namespace kaldi.
+
+#endif